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svq1dec.c
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1 /*
2  * SVQ1 decoder
3  * ported to MPlayer by Arpi <arpi@thot.banki.hu>
4  * ported to libavcodec by Nick Kurshev <nickols_k@mail.ru>
5  *
6  * Copyright (C) 2002 the xine project
7  * Copyright (C) 2002 the ffmpeg project
8  *
9  * SVQ1 Encoder (c) 2004 Mike Melanson <melanson@pcisys.net>
10  *
11  * This file is part of FFmpeg.
12  *
13  * FFmpeg is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU Lesser General Public
15  * License as published by the Free Software Foundation; either
16  * version 2.1 of the License, or (at your option) any later version.
17  *
18  * FFmpeg is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21  * Lesser General Public License for more details.
22  *
23  * You should have received a copy of the GNU Lesser General Public
24  * License along with FFmpeg; if not, write to the Free Software
25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26  */
27 
28 /**
29  * @file
30  * Sorenson Vector Quantizer #1 (SVQ1) video codec.
31  * For more information of the SVQ1 algorithm, visit:
32  * http://www.pcisys.net/~melanson/codecs/
33  */
34 
35 #include "avcodec.h"
36 #include "get_bits.h"
37 #include "h263.h"
38 #include "hpeldsp.h"
39 #include "internal.h"
40 #include "mathops.h"
41 #include "svq1.h"
42 
43 #undef NDEBUG
44 #include <assert.h>
45 
46 static VLC svq1_block_type;
47 static VLC svq1_motion_component;
48 static VLC svq1_intra_multistage[6];
49 static VLC svq1_inter_multistage[6];
50 static VLC svq1_intra_mean;
51 static VLC svq1_inter_mean;
52 
53 /* motion vector (prediction) */
54 typedef struct svq1_pmv_s {
55  int x;
56  int y;
57 } svq1_pmv;
58 
59 typedef struct SVQ1Context {
60  HpelDSPContext hdsp;
61  GetBitContext gb;
62  AVFrame *prev;
63  int width;
64  int height;
65  int frame_code;
66  int nonref; // 1 if the current frame won't be referenced
67 } SVQ1Context;
68 
69 static const uint8_t string_table[256] = {
70  0x00, 0xD5, 0x7F, 0xAA, 0xFE, 0x2B, 0x81, 0x54,
71  0x29, 0xFC, 0x56, 0x83, 0xD7, 0x02, 0xA8, 0x7D,
72  0x52, 0x87, 0x2D, 0xF8, 0xAC, 0x79, 0xD3, 0x06,
73  0x7B, 0xAE, 0x04, 0xD1, 0x85, 0x50, 0xFA, 0x2F,
74  0xA4, 0x71, 0xDB, 0x0E, 0x5A, 0x8F, 0x25, 0xF0,
75  0x8D, 0x58, 0xF2, 0x27, 0x73, 0xA6, 0x0C, 0xD9,
76  0xF6, 0x23, 0x89, 0x5C, 0x08, 0xDD, 0x77, 0xA2,
77  0xDF, 0x0A, 0xA0, 0x75, 0x21, 0xF4, 0x5E, 0x8B,
78  0x9D, 0x48, 0xE2, 0x37, 0x63, 0xB6, 0x1C, 0xC9,
79  0xB4, 0x61, 0xCB, 0x1E, 0x4A, 0x9F, 0x35, 0xE0,
80  0xCF, 0x1A, 0xB0, 0x65, 0x31, 0xE4, 0x4E, 0x9B,
81  0xE6, 0x33, 0x99, 0x4C, 0x18, 0xCD, 0x67, 0xB2,
82  0x39, 0xEC, 0x46, 0x93, 0xC7, 0x12, 0xB8, 0x6D,
83  0x10, 0xC5, 0x6F, 0xBA, 0xEE, 0x3B, 0x91, 0x44,
84  0x6B, 0xBE, 0x14, 0xC1, 0x95, 0x40, 0xEA, 0x3F,
85  0x42, 0x97, 0x3D, 0xE8, 0xBC, 0x69, 0xC3, 0x16,
86  0xEF, 0x3A, 0x90, 0x45, 0x11, 0xC4, 0x6E, 0xBB,
87  0xC6, 0x13, 0xB9, 0x6C, 0x38, 0xED, 0x47, 0x92,
88  0xBD, 0x68, 0xC2, 0x17, 0x43, 0x96, 0x3C, 0xE9,
89  0x94, 0x41, 0xEB, 0x3E, 0x6A, 0xBF, 0x15, 0xC0,
90  0x4B, 0x9E, 0x34, 0xE1, 0xB5, 0x60, 0xCA, 0x1F,
91  0x62, 0xB7, 0x1D, 0xC8, 0x9C, 0x49, 0xE3, 0x36,
92  0x19, 0xCC, 0x66, 0xB3, 0xE7, 0x32, 0x98, 0x4D,
93  0x30, 0xE5, 0x4F, 0x9A, 0xCE, 0x1B, 0xB1, 0x64,
94  0x72, 0xA7, 0x0D, 0xD8, 0x8C, 0x59, 0xF3, 0x26,
95  0x5B, 0x8E, 0x24, 0xF1, 0xA5, 0x70, 0xDA, 0x0F,
96  0x20, 0xF5, 0x5F, 0x8A, 0xDE, 0x0B, 0xA1, 0x74,
97  0x09, 0xDC, 0x76, 0xA3, 0xF7, 0x22, 0x88, 0x5D,
98  0xD6, 0x03, 0xA9, 0x7C, 0x28, 0xFD, 0x57, 0x82,
99  0xFF, 0x2A, 0x80, 0x55, 0x01, 0xD4, 0x7E, 0xAB,
100  0x84, 0x51, 0xFB, 0x2E, 0x7A, 0xAF, 0x05, 0xD0,
101  0xAD, 0x78, 0xD2, 0x07, 0x53, 0x86, 0x2C, 0xF9
102 };
103 
104 #define SVQ1_PROCESS_VECTOR() \
105  for (; level > 0; i++) { \
106  /* process next depth */ \
107  if (i == m) { \
108  m = n; \
109  if (--level == 0) \
110  break; \
111  } \
112  /* divide block if next bit set */ \
113  if (!get_bits1(bitbuf)) \
114  break; \
115  /* add child nodes */ \
116  list[n++] = list[i]; \
117  list[n++] = list[i] + (((level & 1) ? pitch : 1) << ((level >> 1) + 1));\
118  }
119 
120 #define SVQ1_ADD_CODEBOOK() \
121  /* add codebook entries to vector */ \
122  for (j = 0; j < stages; j++) { \
123  n3 = codebook[entries[j]] ^ 0x80808080; \
124  n1 += (n3 & 0xFF00FF00) >> 8; \
125  n2 += n3 & 0x00FF00FF; \
126  } \
127  \
128  /* clip to [0..255] */ \
129  if (n1 & 0xFF00FF00) { \
130  n3 = (n1 >> 15 & 0x00010001 | 0x01000100) - 0x00010001; \
131  n1 += 0x7F007F00; \
132  n1 |= (~n1 >> 15 & 0x00010001 | 0x01000100) - 0x00010001; \
133  n1 &= n3 & 0x00FF00FF; \
134  } \
135  \
136  if (n2 & 0xFF00FF00) { \
137  n3 = (n2 >> 15 & 0x00010001 | 0x01000100) - 0x00010001; \
138  n2 += 0x7F007F00; \
139  n2 |= (~n2 >> 15 & 0x00010001 | 0x01000100) - 0x00010001; \
140  n2 &= n3 & 0x00FF00FF; \
141  }
142 
143 #define SVQ1_CALC_CODEBOOK_ENTRIES(cbook) \
144  codebook = (const uint32_t *)cbook[level]; \
145  if (stages > 0) \
146  bit_cache = get_bits(bitbuf, 4 * stages); \
147  /* calculate codebook entries for this vector */ \
148  for (j = 0; j < stages; j++) { \
149  entries[j] = (((bit_cache >> (4 * (stages - j - 1))) & 0xF) + \
150  16 * j) << (level + 1); \
151  } \
152  mean -= stages * 128; \
153  n4 = (mean << 16) + mean;
154 
155 static int svq1_decode_block_intra(GetBitContext *bitbuf, uint8_t *pixels,
156  int pitch)
157 {
158  uint32_t bit_cache;
159  uint8_t *list[63];
160  uint32_t *dst;
161  const uint32_t *codebook;
162  int entries[6];
163  int i, j, m, n;
164  int mean, stages;
165  unsigned x, y, width, height, level;
166  uint32_t n1, n2, n3, n4;
167 
168  /* initialize list for breadth first processing of vectors */
169  list[0] = pixels;
170 
171  /* recursively process vector */
172  for (i = 0, m = 1, n = 1, level = 5; i < n; i++) {
173  SVQ1_PROCESS_VECTOR();
174 
175  /* destination address and vector size */
176  dst = (uint32_t *)list[i];
177  width = 1 << ((4 + level) / 2);
178  height = 1 << ((3 + level) / 2);
179 
180  /* get number of stages (-1 skips vector, 0 for mean only) */
181  stages = get_vlc2(bitbuf, svq1_intra_multistage[level].table, 3, 3) - 1;
182 
183  if (stages == -1) {
184  for (y = 0; y < height; y++)
185  memset(&dst[y * (pitch / 4)], 0, width);
186  continue; /* skip vector */
187  }
188 
189  if (stages > 0 && level >= 4) {
190  av_dlog(NULL,
191  "Error (svq1_decode_block_intra): invalid vector: stages=%i level=%i\n",
192  stages, level);
193  return AVERROR_INVALIDDATA; /* invalid vector */
194  }
195 
196  mean = get_vlc2(bitbuf, svq1_intra_mean.table, 8, 3);
197 
198  if (stages == 0) {
199  for (y = 0; y < height; y++)
200  memset(&dst[y * (pitch / 4)], mean, width);
201  } else {
202  SVQ1_CALC_CODEBOOK_ENTRIES(ff_svq1_intra_codebooks);
203 
204  for (y = 0; y < height; y++) {
205  for (x = 0; x < width / 4; x++, codebook++) {
206  n1 = n4;
207  n2 = n4;
208  SVQ1_ADD_CODEBOOK()
209  /* store result */
210  dst[x] = n1 << 8 | n2;
211  }
212  dst += pitch / 4;
213  }
214  }
215  }
216 
217  return 0;
218 }
219 
220 static int svq1_decode_block_non_intra(GetBitContext *bitbuf, uint8_t *pixels,
221  int pitch)
222 {
223  uint32_t bit_cache;
224  uint8_t *list[63];
225  uint32_t *dst;
226  const uint32_t *codebook;
227  int entries[6];
228  int i, j, m, n;
229  int mean, stages;
230  int x, y, width, height, level;
231  uint32_t n1, n2, n3, n4;
232 
233  /* initialize list for breadth first processing of vectors */
234  list[0] = pixels;
235 
236  /* recursively process vector */
237  for (i = 0, m = 1, n = 1, level = 5; i < n; i++) {
238  SVQ1_PROCESS_VECTOR();
239 
240  /* destination address and vector size */
241  dst = (uint32_t *)list[i];
242  width = 1 << ((4 + level) / 2);
243  height = 1 << ((3 + level) / 2);
244 
245  /* get number of stages (-1 skips vector, 0 for mean only) */
246  stages = get_vlc2(bitbuf, svq1_inter_multistage[level].table, 3, 2) - 1;
247 
248  if (stages == -1)
249  continue; /* skip vector */
250 
251  if ((stages > 0) && (level >= 4)) {
252  av_dlog(NULL,
253  "Error (svq1_decode_block_non_intra): invalid vector: stages=%i level=%i\n",
254  stages, level);
255  return AVERROR_INVALIDDATA; /* invalid vector */
256  }
257 
258  mean = get_vlc2(bitbuf, svq1_inter_mean.table, 9, 3) - 256;
259 
260  SVQ1_CALC_CODEBOOK_ENTRIES(ff_svq1_inter_codebooks);
261 
262  for (y = 0; y < height; y++) {
263  for (x = 0; x < width / 4; x++, codebook++) {
264  n3 = dst[x];
265  /* add mean value to vector */
266  n1 = n4 + ((n3 & 0xFF00FF00) >> 8);
267  n2 = n4 + (n3 & 0x00FF00FF);
268  SVQ1_ADD_CODEBOOK()
269  /* store result */
270  dst[x] = n1 << 8 | n2;
271  }
272  dst += pitch / 4;
273  }
274  }
275  return 0;
276 }
277 
278 static int svq1_decode_motion_vector(GetBitContext *bitbuf, svq1_pmv *mv,
279  svq1_pmv **pmv)
280 {
281  int diff;
282  int i;
283 
284  for (i = 0; i < 2; i++) {
285  /* get motion code */
286  diff = get_vlc2(bitbuf, svq1_motion_component.table, 7, 2);
287  if (diff < 0)
288  return AVERROR_INVALIDDATA;
289  else if (diff) {
290  if (get_bits1(bitbuf))
291  diff = -diff;
292  }
293 
294  /* add median of motion vector predictors and clip result */
295  if (i == 1)
296  mv->y = sign_extend(diff + mid_pred(pmv[0]->y, pmv[1]->y, pmv[2]->y), 6);
297  else
298  mv->x = sign_extend(diff + mid_pred(pmv[0]->x, pmv[1]->x, pmv[2]->x), 6);
299  }
300 
301  return 0;
302 }
303 
304 static void svq1_skip_block(uint8_t *current, uint8_t *previous,
305  int pitch, int x, int y)
306 {
307  uint8_t *src;
308  uint8_t *dst;
309  int i;
310 
311  src = &previous[x + y * pitch];
312  dst = current;
313 
314  for (i = 0; i < 16; i++) {
315  memcpy(dst, src, 16);
316  src += pitch;
317  dst += pitch;
318  }
319 }
320 
321 static int svq1_motion_inter_block(HpelDSPContext *hdsp, GetBitContext *bitbuf,
322  uint8_t *current, uint8_t *previous,
323  int pitch, svq1_pmv *motion, int x, int y,
324  int width, int height)
325 {
326  uint8_t *src;
327  uint8_t *dst;
328  svq1_pmv mv;
329  svq1_pmv *pmv[3];
330  int result;
331 
332  /* predict and decode motion vector */
333  pmv[0] = &motion[0];
334  if (y == 0) {
335  pmv[1] =
336  pmv[2] = pmv[0];
337  } else {
338  pmv[1] = &motion[x / 8 + 2];
339  pmv[2] = &motion[x / 8 + 4];
340  }
341 
342  result = svq1_decode_motion_vector(bitbuf, &mv, pmv);
343  if (result)
344  return result;
345 
346  motion[0].x =
347  motion[x / 8 + 2].x =
348  motion[x / 8 + 3].x = mv.x;
349  motion[0].y =
350  motion[x / 8 + 2].y =
351  motion[x / 8 + 3].y = mv.y;
352 
353  mv.x = av_clip(mv.x, -2 * x, 2 * (width - x - 16));
354  mv.y = av_clip(mv.y, -2 * y, 2 * (height - y - 16));
355 
356  src = &previous[(x + (mv.x >> 1)) + (y + (mv.y >> 1)) * pitch];
357  dst = current;
358 
359  hdsp->put_pixels_tab[0][(mv.y & 1) << 1 | (mv.x & 1)](dst, src, pitch, 16);
360 
361  return 0;
362 }
363 
364 static int svq1_motion_inter_4v_block(HpelDSPContext *hdsp, GetBitContext *bitbuf,
365  uint8_t *current, uint8_t *previous,
366  int pitch, svq1_pmv *motion, int x, int y,
367  int width, int height)
368 {
369  uint8_t *src;
370  uint8_t *dst;
371  svq1_pmv mv;
372  svq1_pmv *pmv[4];
373  int i, result;
374 
375  /* predict and decode motion vector (0) */
376  pmv[0] = &motion[0];
377  if (y == 0) {
378  pmv[1] =
379  pmv[2] = pmv[0];
380  } else {
381  pmv[1] = &motion[(x / 8) + 2];
382  pmv[2] = &motion[(x / 8) + 4];
383  }
384 
385  result = svq1_decode_motion_vector(bitbuf, &mv, pmv);
386  if (result)
387  return result;
388 
389  /* predict and decode motion vector (1) */
390  pmv[0] = &mv;
391  if (y == 0) {
392  pmv[1] =
393  pmv[2] = pmv[0];
394  } else {
395  pmv[1] = &motion[(x / 8) + 3];
396  }
397  result = svq1_decode_motion_vector(bitbuf, &motion[0], pmv);
398  if (result)
399  return result;
400 
401  /* predict and decode motion vector (2) */
402  pmv[1] = &motion[0];
403  pmv[2] = &motion[(x / 8) + 1];
404 
405  result = svq1_decode_motion_vector(bitbuf, &motion[(x / 8) + 2], pmv);
406  if (result)
407  return result;
408 
409  /* predict and decode motion vector (3) */
410  pmv[2] = &motion[(x / 8) + 2];
411  pmv[3] = &motion[(x / 8) + 3];
412 
413  result = svq1_decode_motion_vector(bitbuf, pmv[3], pmv);
414  if (result)
415  return result;
416 
417  /* form predictions */
418  for (i = 0; i < 4; i++) {
419  int mvx = pmv[i]->x + (i & 1) * 16;
420  int mvy = pmv[i]->y + (i >> 1) * 16;
421 
422  // FIXME: clipping or padding?
423  mvx = av_clip(mvx, -2 * x, 2 * (width - x - 8));
424  mvy = av_clip(mvy, -2 * y, 2 * (height - y - 8));
425 
426  src = &previous[(x + (mvx >> 1)) + (y + (mvy >> 1)) * pitch];
427  dst = current;
428 
429  hdsp->put_pixels_tab[1][((mvy & 1) << 1) | (mvx & 1)](dst, src, pitch, 8);
430 
431  /* select next block */
432  if (i & 1)
433  current += 8 * (pitch - 1);
434  else
435  current += 8;
436  }
437 
438  return 0;
439 }
440 
441 static int svq1_decode_delta_block(AVCodecContext *avctx, HpelDSPContext *hdsp,
442  GetBitContext *bitbuf,
443  uint8_t *current, uint8_t *previous,
444  int pitch, svq1_pmv *motion, int x, int y,
445  int width, int height)
446 {
447  uint32_t block_type;
448  int result = 0;
449 
450  /* get block type */
451  block_type = get_vlc2(bitbuf, svq1_block_type.table, 2, 2);
452 
453  /* reset motion vectors */
454  if (block_type == SVQ1_BLOCK_SKIP || block_type == SVQ1_BLOCK_INTRA) {
455  motion[0].x =
456  motion[0].y =
457  motion[x / 8 + 2].x =
458  motion[x / 8 + 2].y =
459  motion[x / 8 + 3].x =
460  motion[x / 8 + 3].y = 0;
461  }
462 
463  switch (block_type) {
464  case SVQ1_BLOCK_SKIP:
465  svq1_skip_block(current, previous, pitch, x, y);
466  break;
467 
468  case SVQ1_BLOCK_INTER:
469  result = svq1_motion_inter_block(hdsp, bitbuf, current, previous,
470  pitch, motion, x, y, width, height);
471 
472  if (result != 0) {
473  av_dlog(avctx, "Error in svq1_motion_inter_block %i\n", result);
474  break;
475  }
476  result = svq1_decode_block_non_intra(bitbuf, current, pitch);
477  break;
478 
479  case SVQ1_BLOCK_INTER_4V:
480  result = svq1_motion_inter_4v_block(hdsp, bitbuf, current, previous,
481  pitch, motion, x, y, width, height);
482 
483  if (result != 0) {
484  av_dlog(avctx, "Error in svq1_motion_inter_4v_block %i\n", result);
485  break;
486  }
487  result = svq1_decode_block_non_intra(bitbuf, current, pitch);
488  break;
489 
490  case SVQ1_BLOCK_INTRA:
491  result = svq1_decode_block_intra(bitbuf, current, pitch);
492  break;
493  }
494 
495  return result;
496 }
497 
498 static void svq1_parse_string(GetBitContext *bitbuf, uint8_t *out)
499 {
500  uint8_t seed;
501  int i;
502 
503  out[0] = get_bits(bitbuf, 8);
504  seed = string_table[out[0]];
505 
506  for (i = 1; i <= out[0]; i++) {
507  out[i] = get_bits(bitbuf, 8) ^ seed;
508  seed = string_table[out[i] ^ seed];
509  }
510 }
511 
512 static int svq1_decode_frame_header(AVCodecContext *avctx, AVFrame *frame)
513 {
514  SVQ1Context *s = avctx->priv_data;
515  GetBitContext *bitbuf = &s->gb;
516  int frame_size_code;
517  int width = s->width;
518  int height = s->height;
519 
520  skip_bits(bitbuf, 8); /* temporal_reference */
521 
522  /* frame type */
523  s->nonref = 0;
524  switch (get_bits(bitbuf, 2)) {
525  case 0:
526  frame->pict_type = AV_PICTURE_TYPE_I;
527  break;
528  case 2:
529  s->nonref = 1;
530  case 1:
531  frame->pict_type = AV_PICTURE_TYPE_P;
532  break;
533  default:
534  av_log(avctx, AV_LOG_ERROR, "Invalid frame type.\n");
535  return AVERROR_INVALIDDATA;
536  }
537 
538  if (frame->pict_type == AV_PICTURE_TYPE_I) {
539  /* unknown fields */
540  if (s->frame_code == 0x50 || s->frame_code == 0x60) {
541  int csum = get_bits(bitbuf, 16);
542 
543  csum = ff_svq1_packet_checksum(bitbuf->buffer,
544  bitbuf->size_in_bits >> 3,
545  csum);
546 
547  av_dlog(avctx, "%s checksum (%02x) for packet data\n",
548  (csum == 0) ? "correct" : "incorrect", csum);
549  }
550 
551  if ((s->frame_code ^ 0x10) >= 0x50) {
552  uint8_t msg[256];
553 
554  svq1_parse_string(bitbuf, msg);
555 
556  av_log(avctx, AV_LOG_INFO,
557  "embedded message:\n%s\n", (char *)msg);
558  }
559 
560  skip_bits(bitbuf, 2);
561  skip_bits(bitbuf, 2);
562  skip_bits1(bitbuf);
563 
564  /* load frame size */
565  frame_size_code = get_bits(bitbuf, 3);
566 
567  if (frame_size_code == 7) {
568  /* load width, height (12 bits each) */
569  width = get_bits(bitbuf, 12);
570  height = get_bits(bitbuf, 12);
571 
572  if (!width || !height)
573  return AVERROR_INVALIDDATA;
574  } else {
575  /* get width, height from table */
576  width = ff_svq1_frame_size_table[frame_size_code][0];
577  height = ff_svq1_frame_size_table[frame_size_code][1];
578  }
579  }
580 
581  /* unknown fields */
582  if (get_bits1(bitbuf)) {
583  skip_bits1(bitbuf); /* use packet checksum if (1) */
584  skip_bits1(bitbuf); /* component checksums after image data if (1) */
585 
586  if (get_bits(bitbuf, 2) != 0)
587  return AVERROR_INVALIDDATA;
588  }
589 
590  if (get_bits1(bitbuf)) {
591  skip_bits1(bitbuf);
592  skip_bits(bitbuf, 4);
593  skip_bits1(bitbuf);
594  skip_bits(bitbuf, 2);
595 
596  while (get_bits1(bitbuf))
597  skip_bits(bitbuf, 8);
598  }
599 
600  s->width = width;
601  s->height = height;
602  return 0;
603 }
604 
605 static int svq1_decode_frame(AVCodecContext *avctx, void *data,
606  int *got_frame, AVPacket *avpkt)
607 {
608  const uint8_t *buf = avpkt->data;
609  int buf_size = avpkt->size;
610  SVQ1Context *s = avctx->priv_data;
611  AVFrame *cur = data;
612  uint8_t *current;
613  int result, i, x, y, width, height;
614  svq1_pmv *pmv;
615 
616  /* initialize bit buffer */
617  init_get_bits8(&s->gb, buf, buf_size);
618 
619  /* decode frame header */
620  s->frame_code = get_bits(&s->gb, 22);
621 
622  if ((s->frame_code & ~0x70) || !(s->frame_code & 0x60))
623  return AVERROR_INVALIDDATA;
624 
625  /* swap some header bytes (why?) */
626  if (s->frame_code != 0x20) {
627  uint32_t *src = (uint32_t *)(buf + 4);
628 
629  if (buf_size < 36)
630  return AVERROR_INVALIDDATA;
631 
632  for (i = 0; i < 4; i++)
633  src[i] = ((src[i] << 16) | (src[i] >> 16)) ^ src[7 - i];
634  }
635 
636  result = svq1_decode_frame_header(avctx, cur);
637  if (result != 0) {
638  av_dlog(avctx, "Error in svq1_decode_frame_header %i\n", result);
639  return result;
640  }
641  avcodec_set_dimensions(avctx, s->width, s->height);
642 
643  if ((avctx->skip_frame >= AVDISCARD_NONREF && s->nonref) ||
644  (avctx->skip_frame >= AVDISCARD_NONKEY &&
645  cur->pict_type != AV_PICTURE_TYPE_I) ||
646  avctx->skip_frame >= AVDISCARD_ALL)
647  return buf_size;
648 
649  result = ff_get_buffer(avctx, cur, s->nonref ? 0 : AV_GET_BUFFER_FLAG_REF);
650  if (result < 0)
651  return result;
652 
653  pmv = av_malloc((FFALIGN(s->width, 16) / 8 + 3) * sizeof(*pmv));
654  if (!pmv)
655  return AVERROR(ENOMEM);
656 
657  /* decode y, u and v components */
658  for (i = 0; i < 3; i++) {
659  int linesize = cur->linesize[i];
660  if (i == 0) {
661  width = FFALIGN(s->width, 16);
662  height = FFALIGN(s->height, 16);
663  } else {
664  if (avctx->flags & CODEC_FLAG_GRAY)
665  break;
666  width = FFALIGN(s->width / 4, 16);
667  height = FFALIGN(s->height / 4, 16);
668  }
669 
670  current = cur->data[i];
671 
672  if (cur->pict_type == AV_PICTURE_TYPE_I) {
673  /* keyframe */
674  for (y = 0; y < height; y += 16) {
675  for (x = 0; x < width; x += 16) {
676  result = svq1_decode_block_intra(&s->gb, &current[x],
677  linesize);
678  if (result) {
679  av_log(avctx, AV_LOG_ERROR,
680  "Error in svq1_decode_block %i (keyframe)\n",
681  result);
682  goto err;
683  }
684  }
685  current += 16 * linesize;
686  }
687  } else {
688  /* delta frame */
689  uint8_t *previous = s->prev->data[i];
690  if (!previous ||
691  s->prev->width != s->width || s->prev->height != s->height) {
692  av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
693  result = AVERROR_INVALIDDATA;
694  goto err;
695  }
696 
697  memset(pmv, 0, ((width / 8) + 3) * sizeof(svq1_pmv));
698 
699  for (y = 0; y < height; y += 16) {
700  for (x = 0; x < width; x += 16) {
701  result = svq1_decode_delta_block(avctx, &s->hdsp,
702  &s->gb, &current[x],
703  previous, linesize,
704  pmv, x, y, width, height);
705  if (result != 0) {
706  av_dlog(avctx,
707  "Error in svq1_decode_delta_block %i\n",
708  result);
709  goto err;
710  }
711  }
712 
713  pmv[0].x =
714  pmv[0].y = 0;
715 
716  current += 16 * linesize;
717  }
718  }
719  }
720 
721  if (!s->nonref) {
722  av_frame_unref(s->prev);
723  result = av_frame_ref(s->prev, cur);
724  if (result < 0)
725  goto err;
726  }
727 
728  *got_frame = 1;
729  result = buf_size;
730 
731 err:
732  av_free(pmv);
733  return result;
734 }
735 
736 static av_cold int svq1_decode_init(AVCodecContext *avctx)
737 {
738  SVQ1Context *s = avctx->priv_data;
739  int i;
740  int offset = 0;
741 
742  s->prev = avcodec_alloc_frame();
743  if (!s->prev)
744  return AVERROR(ENOMEM);
745 
746  s->width = avctx->width + 3 & ~3;
747  s->height = avctx->height + 3 & ~3;
748  avctx->pix_fmt = AV_PIX_FMT_YUV410P;
749 
750  ff_hpeldsp_init(&s->hdsp, avctx->flags);
751 
752  INIT_VLC_STATIC(&svq1_block_type, 2, 4,
753  &ff_svq1_block_type_vlc[0][1], 2, 1,
754  &ff_svq1_block_type_vlc[0][0], 2, 1, 6);
755 
756  INIT_VLC_STATIC(&svq1_motion_component, 7, 33,
757  &ff_mvtab[0][1], 2, 1,
758  &ff_mvtab[0][0], 2, 1, 176);
759 
760  for (i = 0; i < 6; i++) {
761  static const uint8_t sizes[2][6] = { { 14, 10, 14, 18, 16, 18 },
762  { 10, 10, 14, 14, 14, 16 } };
763  static VLC_TYPE table[168][2];
764  svq1_intra_multistage[i].table = &table[offset];
765  svq1_intra_multistage[i].table_allocated = sizes[0][i];
766  offset += sizes[0][i];
767  init_vlc(&svq1_intra_multistage[i], 3, 8,
768  &ff_svq1_intra_multistage_vlc[i][0][1], 2, 1,
769  &ff_svq1_intra_multistage_vlc[i][0][0], 2, 1,
770  INIT_VLC_USE_NEW_STATIC);
771  svq1_inter_multistage[i].table = &table[offset];
772  svq1_inter_multistage[i].table_allocated = sizes[1][i];
773  offset += sizes[1][i];
774  init_vlc(&svq1_inter_multistage[i], 3, 8,
775  &ff_svq1_inter_multistage_vlc[i][0][1], 2, 1,
776  &ff_svq1_inter_multistage_vlc[i][0][0], 2, 1,
777  INIT_VLC_USE_NEW_STATIC);
778  }
779 
780  INIT_VLC_STATIC(&svq1_intra_mean, 8, 256,
781  &ff_svq1_intra_mean_vlc[0][1], 4, 2,
782  &ff_svq1_intra_mean_vlc[0][0], 4, 2, 632);
783 
784  INIT_VLC_STATIC(&svq1_inter_mean, 9, 512,
785  &ff_svq1_inter_mean_vlc[0][1], 4, 2,
786  &ff_svq1_inter_mean_vlc[0][0], 4, 2, 1434);
787 
788  return 0;
789 }
790 
791 static av_cold int svq1_decode_end(AVCodecContext *avctx)
792 {
793  SVQ1Context *s = avctx->priv_data;
794 
795  av_frame_free(&s->prev);
796 
797  return 0;
798 }
799 
800 static void svq1_flush(AVCodecContext *avctx)
801 {
802  SVQ1Context *s = avctx->priv_data;
803 
804  av_frame_unref(s->prev);
805 }
806 
807 AVCodec ff_svq1_decoder = {
808  .name = "svq1",
809  .long_name = NULL_IF_CONFIG_SMALL("Sorenson Vector Quantizer 1 / Sorenson Video 1 / SVQ1"),
810  .type = AVMEDIA_TYPE_VIDEO,
811  .id = AV_CODEC_ID_SVQ1,
812  .priv_data_size = sizeof(SVQ1Context),
813  .init = svq1_decode_init,
814  .close = svq1_decode_end,
815  .decode = svq1_decode_frame,
816  .capabilities = CODEC_CAP_DR1,
817  .flush = svq1_flush,
818  .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV410P,
819  AV_PIX_FMT_NONE },
820 };
Generated on Sat Jan 25 2014 19:51:55 for FFmpeg by   doxygen 1.8.2